Method for soluble expression and purification of hydrophobin

Abstract

A method of expressing hydrophobin in a soluble form and a method of purifying hydrophobin, and more particularly, to a method of expressing a recombinant fusion protein including hydrophobin in a soluble form in a host cell and then purifying the expressed recombinant fusion protein are provided.

The invention claimed is: 
     
       1. A method of purifying a recombinant fusion protein expressed in a soluble form, the method comprising:
 a) expressing the recombinant fusion protein in soluble form by transforming a bacterial host cell with a vector into which a base sequence encoding the recombinant fusion protein is introduced to form a transformed cell, the recombinant fusion protein including: a target protein; and a ramp tag for controlling a translation speed and tRNA recruiting, fused at an N-terminal of the target protein; and 
 b) purifying the expressed recombinant fusion protein, wherein the target protein is hydrophobin, wherein b) includes:
 b1) suspending the transformed cell to form a suspended cell and lysing and centrifuging the suspended cell to obtain a first supernatant; 
 b2) shaking and then centrifuging a first mixture obtained by adding a first solvent to the first supernatant to obtain a second supernatant; and 
 b3) shaking and then centrifuging a second mixture obtained by adding a second solvent to the second supernatant to recover the target protein, wherein each of the first solvent and the second solvent is isopropyl alcohol, and wherein a volume ratio of the isopropyl alcohol to the first supernatant and second supernatant is 1:2 to 1:3, respectively, wherein the target protein is DewA. 
 
 
     
     
       2. The method of  claim 1 , wherein the target protein consists of an amino acid sequence of SEQ ID NO: 8 or 10. 
     
     
       3. The method of  claim 1 , wherein the bacterial host cell is a bacterium belonging to  Escherichia  sp.,  Salmonellae  sp.,  Yersinia  sp.,  Shigella  sp.,  Enterobacter  sp.,  Pseudomonas  sp.,  Proteus  sp., or  Klebsiella  sp. 
     
     
       4. The method of  claim 1 , wherein the ramp tag consists of an amino acid sequence of SEQ ID NO: 5.